The last few years have been quite challenging for the chemical industry in Asia. Vibration of oil prices, regulatory pressures, global climate plans and competition, and changing demographics have a huge impact on chemical industry. In the last years chemical industry companies are working on two major production concepts to further improve their production of chemicals, materials or bio-technology products: cyclic economy and modularized production. The general goal of these activities is to produce faster, with a higher quality and in a less wasteful manner. The chemical industry is facing an increasing demand from fast growing and vibrant markets in Asia and a trend to customized specialty and fine chemicals. Asian chemical companies face different challenge from those in US, Europe and Middle East, such as energy-deficiency, high cost of energy and raw materials, strengthening environmental regulations, increasing labor-cost, etc.
The circular economy in developing countries can increase productivity and economic growth, improving the quality and quantity of employment, and save lives, by reducing environmental impacts such as water and air pollution. For most Asian countries there is huge potential to improve productivity by using resources more efficiently. However, many chemical plants in East Asia are old and need renovate to achieve new standard. With efficient technologies, there are huge business opportunities for companies.
The demand for lithium-ion batteries (LIBs) is expected to increase dramatically in the next decades because of the growing EV market. As a result, a large volume of batteries will reach their end-of-primary-life in the near future. However, the spent battery may still retain their capacity, which could be serviceable in its second-life, e.g. for the stationary energy system, or remanufactured to be used again in EVs. The LIB supply chain might benefit from reducing raw material consumption, if LIBs are reused through refurbishing, remanufacturing, or recycled. The reuse and recycle of LIB will also facilitate waste management by the recovery of all valued battery components to contribute to a circular economy. To devise a circular economy strategy for the LIB system, the material flows and the environmental impacts associated with their life cycle including manufacturing, use, and end-of-life phases should be assessed. Although numerous studies on the environmental impact of LIB production are available, the existing primary life cycle inventory data is often difficult to trace back, which is inflexible to discuss the different properties of LIB and energy demand related to the manufacturing process. The different LIB chemistries that have different combinations of metals, will make the material and energy consumption in production process vary. In this study, a bottom-up inventory model of LIB production, which enables to estimate the material requirements, energy demands and the associated environmental impacts such as greenhouse gas (GHG) emission, is developed. Here, we demonstrate that with this modeling approach, it becomes possible to assist devising a circular economy strategy from environmental impact perspective, reflecting envisioned future circumstances e.g. decarbonization of electricity generation, by coupling with a material flow analysis model.
MgO@ZIF-8 catalysts with various MgO loadings (10-50 wt%) were prepared through a wet-impregnation and calcination process. The physicochemical properties of MgO@ZIF-8 catalysts were characterized using atomic absorption spectroscopy, X-ray diffraction, , nitrogen sorption isotherms, field-emission transmission electron microscopy, and thermogravimetric analysis. It is found that MgO nanoparticles could deposit onto the ZIF-8 surface with high atom efficiency and little influence on the ZIF-8 structure. It is suggested that the surface sites and microporosity of ZIF-8 support facilitate the deposition of Mg precursor and subsequent formation of MgO nanoparticles. MgO@ZIF-8 catalysts were tested for catalytic transesterification of glycerol and dimethyl carbonate. It is found that the 50 wt% MgO@ZIF-8 catalyst display an improved catalytic activity on glycerol carbonate production than those of MgO and ZIF-8. Furthermore, the MgO@ZIF-8 catalysts showed higher catalytic activities than their physically-mixed counterparts. These results suggest a synergistic effect between MgO and ZIF-8, which is explained by an acid-base bifunctional catalysis mechanism.
Inclusivity is a vital aspect of sustainable development which has been emerging as a challenge in economically developed, matured societies. In Japan, the rural areas are suffering from lagged economic development, the aging society, and declining population. Tackling sustainability challenges without leaving out problems in these areas are essential, but requires a new approach in industrial development. Creating sufficiently productive and profitable systems that utilize locally-available resources are seen as a potential key to vitalize the rural areas while tackling the SGDs.
Attempts to collect and study all the relevant information can lead to an excessive requirement on time and effort in the early stages of a design project. Because some of the unknowns are more important than others, prioritization of the unknown factors that requires a closer investigation can potentially reduce the time and cost for the initial design. In this study, a system synthesis method that generates combinations of resources, technology, and products, ranked in order, formulated as a MILP is applied to indirectly prioritize the unknowns, while comprehensively exploring the combinations of the known options.
The higher ranked systems will include some designs that are impractical due to missing practical constraints. The ranked list of the systems will help to identify overlooked constraints, starting from more important ones. The unknowns that are related to the identified constraints are then studied and added in the systems synthesis model. After several iterations, all the critical unknowns are studied to describe the key constraints and the most promising systems can be proposed.
Features added to existing studies, i.e., 1) consideration of the combinations at its suboptimal capacity of processing, 2) incorporation of material storage equipment and efficiency in order to overcome the seasonal variations in availability of resources and the demand of products, will be introduced with simple examples.
Methyltetrahydrofuran (MTHF) have received great attention for combustion system applications, because it can be readily used in blends with gasoline and diesel without major engine modifications. In this study, as a sustainable platform chemical for the biofuels and biochemicals, conversion of MTHF from lignocellulosic biomass was studied. For the conversion of MTHF, domestic grown woody biomass such as pine and oak in Korea were firstly treated by chemical and thermal treatment for the production of C6 substrate and further production of levulinic acid (LA) via 5-hydroxymethylfurfural (HMF) intermediate, which was then subjected to the catalytic conversion for the conversion of MTHF.
At the beginning of the conversion process, alkaline reagents (ex. sodium hydroxide and ammonium hydroxide) were applied to produce C6-rich substrate (>70%), which was then converted by de-hydration and re-hydration reactions into LA using sulfuric acid (1~5 wt%) at high temperature (121~190 °C). For the conversion of MTHF via gamma-valero lactone (GVL) intermediate using de-hydration and hydrogenation reactions under high temperature and pressure conditions, high-efficiency heterogeneous bimetal catalyst was synthesized and attempted for precious metal replacement in the presence of the effective CTH (catalytic transfer hydrogenation) solutions.
In this paper, conversion yields of C6, LA, and MTHF were evaluated and reported under various reaction conditions. For the increased MTHF production, various catalytic reaction conditions pertinent to effective and viable process were explored and discussed.
A continuous twin screw-driven reactor (CTSR) can provide a unique and efficient reaction environment for the pretreatment of lignocellulosic biomass. CTSR has the ability to provide high shear, rapid heat transfer, effective mixing. The thermo-mechanical energy provided by the continuously stirred screws in CTSR, which causes the shear forces, can be applied to the continuous pulverization of biomass, thus improving the overall rate of biomass conversion. Considering the high labor intensity and energy requirement of batch pretreatment, a CTSR process has great potential for increasing the efficiency of biomass pretreatment.
CTSR for the pretreatment of biomass would be practicable and useful for large scale production because it affords high-efficiency pulverization by a high shearing force, and adaptability to many different process modifications, such as application of simultaneous physical and chemical treatments using other catalysts. The performance of biomass pretreatment through CTSR is a complex function of screw rotational speed, throughput, and screw configuration etc. The interaction between different processing parameters leads to complex functions of shear conditions and reaction severities, both of which affect pretreatment performance.
With the aim to provide a further insight into CTSR pretreatment, enlarged CTSR to 100 kg/day scaled was developed and demonstrated. Mathematical modelling for fluid dynamics and heat transfer were developed by a set of ordinary differential equations (ODE) based on first-principle models. The resulting ODE set was experimentally validated using model biomass (sawdust) as feedstock. The kinetic parameters of biomass pretreatment performance were estimated from experimental results.
These results will contribute to improved reactor design and scale-up tasks, and in turn, to the successful deployment of novel industrial-scale technologies for biomass pretreatment.
Industrial symbiosis with unused local biomass can be one of a key approach from the viewpoint of sustainability of agriculture, forestry and the regions. Planning biomass-based industrial symbiosis necessitates hard decisions including long-term visioning of the regions and consensus building among various stakeholders such as agriculture, forestry, energy supplier, local government, and technology researchers. Chemical engineering approach with modeling and simulation can strongly support such planning process. The planning process of the symbiosis to be supported has not been well established nor systematized in previous studies. In this study, systematic planning process for biomass-based industrial symbiosis was proposed and the requirements of its supporting mechanisms were defined. The planning process was structured as the series of sub-activities based on the re-analysis of the case studies for planning industrial symbiosis integrating cane sugar industry and local forestry on a specific region. Modeling and simulation of regional energy systems with multiple co-generation plants fueled by local biomass from the industries were performed in the case studies. The planning process was defined that consists of the activities of planning tasks, i.e., <Examine present system>, <Generate alternatives>, <Simulate flows> and <Evaluate>. Additionally, these tasks are controlled by <Manage>, and the proposal of the symbiosis plan as the product by the tasks are checked by <Review>. These activities of planning tasks can be supported by the mechanisms, such as IoT monitoring system, technology matching tool, flow simulator and evaluation tool. The applicability of the planning process and the supporting mechanisms is to be discussed through new case studies in other regions. Human networks among region, academia and industries have significant roles to implement the symbiosis plans toward the regional sustainable visions even if the supporting tools highly developed in future.
To effectively mobilize the limited time and resources for the accomplishment of a transition towards sustainability, efforts on a technology development must be made in a manner coherent with other efforts under a vision on the sustainable society. Technology Roadmapping (TR) is amongst the several approaches that may cross-link a technology development with a future vision. Here, I provide an example of assisting TR by exploring the balances between technology performances with other exogenous variables in the future society with a dynamic Material Flow Analysis (dMFA).
In Japan, a future target of the power supply configuration (energy mix) based on the massive introduction of renewable energy has been advocated, in which Photovoltaics (PV) accounts for ~7% of the total power generation capacity, i.e., approximately 30% of the renewable power sources. On the other hand, a substantial amount of Si type PV (Si-PV) would reach their End of Life (EoL) soon. Therefore, the development of a technology recovering Si from EoL Si-PV may effectively respond to the demand to achieve the target without spending a massive amount of energy for Si purification from Silica sand. To consider such technology, a long-term evaluation of benefits and impacts on both economy and environment is required to invite stakeholders to jointly materialize the reasonable and comprehensive roadmap. Here, our team conducted a time series quantification of flows and stocks in an envisioned Si-circulation system. Then, we deduce the development directions as a roadmap with respect to various design variables (ex. an average lifetime of product) on the basis of multiple criteria (e.g., the net-energy acquisition and net-CO2 avoidance). With this example, I aim to highlight the potentials and challenges of vision-oriented technology development for the achievement of SDGs 9: Industry, Innovations and Infrastructure and SDGs 7: Affordable and Clean Energy.
A hydrogen supply chain consists of the production, transportation, storage, and distribution of hydrogen as an energy source. A variety of decision variables should be determined along the supply chain including technological options of producing hydrogen, phase of hydrogen, location and capacity of treating facility, and the amount of transportation between the regions. The optimization problem can be effectively formulated and solved for this complex systems. In this presentation, we have investigated for the optimal strategy for hydrogen supply chain and present the optimal solution to the case of South Korea.
CuInS2 (CIS) is a solar absorber with the energy band gap of 1.5 eV, suitable for hydrogen production from water splitting. The types of conductivity (n- or p-type) of CIS photoelectrode can be tuned as a function of Cu/In concentration ratio. In this report, CIS films were deposited using spray deposition onto ITO-coated glass substrates from aqueous solutions consisted of copper (II) chloride, indium chloride and thiourea. First, the ratios of the precursor solutions were varied and the transition from n- to p-type conductivity was observed. Next, Zn-doped CuInS2 (Zn-CIS) thin films exhibited p-type conductivity from electrochemical measurements. XRD results reveal the cubic-structured Zn-CIS films. The successive shift of XRD patterns toward higher angles with zinc molar fraction is evident of the formation of Cu-In-Zn-S solid solution. LSV results shows that the photocurrent density of Zn-CIS film reached 2.5 mA/cm2, higher than the bare CIS (0.3 mA/cm2). Finally, n-type ITO thin film was deposited onto the p-type CIS. Here, we want to demonstrate that suitable match of the p-n junction can create a high efficient photoelectrode for hydrogen production from water.
The electrochemical reduction of CO2 recently draws great attention because of its sustainable capability of producing fuels and chemicals. However, the high over potential of CO2 reduction reaction-oxygen evolution reaction (CO2RR-OER) have been pointed out as an obstacle of commercialization. Herein, we propose electrochemical co-production of CO2RR and oxidative reforming of organic materials. The oxidative reforming of organic materials not only potentially reduces operating cell voltages but also improves system economic feasibility by producing more valuable chemicals than oxygen. We introduces an automated and generalized platform for the techno- economic alanysis (TEA) of electrochemical coproduction system and investigate the 16 candidates of CO2RR for cathode and 18 candidates of organic oxidation reaction for anode. The TES platform generates a product oriented process systems design including reaction, separation, and recycle. Global sensitivity analysis of Faraday efficiency, current density, and overpotential for the levelized cost of each product to understand which index should be improved first. Hydrogen, carbon monoxide, formic acid, glycoladehyde, ally alcohol, ethylene glycol, acetic acid, and propanol can be the promising candidate for the CO2RR and 2,5-Furandicarboxylic acid (FDCA), oxalic acid, acrylic acid, glycolic acid, lactic acid, 2-furoic acid, and ethyl acetate can be the promising candidate for the anodic oxidation.
